Dehydration
If you are dehydrated, it means your body has lost more fluids than you have drunk. If it gets worse, it can be a serious problem and life threatening. Babies, children and older people are more at risk of dehydration and its serious effects.
Causes of dehydration
You can become dehydrated if you:
- are unwell, such as with runny poo (diarrhoea) or being sick (vomiting) — gastroenteritis
- have a fever (high temperature)
- have not eaten enough or drunk enough fluids
- have been in very hot conditions
- exercise heavily or work hard physically without drinking enough fluids
- have kidney disease or diabetes, which can cause you to wee (urinate) more often
- need to take certain medicines, such as water pills (diuretics) — these can cause your body to lose water
- drink too much alcohol — alcohol makes you wee more.
Symptoms of mild dehydration
If you are a healthy adult, your thirst will usually let you know you are mildly dehydrated and need more water. You might also notice your wee is darker.
Symptoms of moderate and severe dehydration
Symptoms of moderate dehydration include:
- weeing less often
- dark-yellow wee colour
- dry mouth, lips and tongue
- faster heart rate
- feeling sick or being sick (nausea and vomiting)
- dizziness and feeling faint
- poorer concentration and memory, slower reactions
- headaches
- muscle cramps or spasms
- sunken eyes
- weakness.
Signs of severe dehydration include:
- seizures
- confusion
- severe weakness, dizziness or tiredness
- a reduced level of consciousness
- dry, red (flushed), hot skin without sweating.
Dehydration in older people
Older people cannot always rely on thirst as a warning sign. If you are an older person:
- your thirst sensation may be weaker
- your body's fluid reserve is smaller
- your body's ability to retain water is lower.
This can be made worse by conditions such as diabetes and dementia, by certain medicines or memory or mobility problems which prevent you getting enough to drink.
Older people may not realise they need to drink more fluids. If you are older, you are at a higher risk for becoming dehydrated.
Dehydration in babies and children
If your pēpi is dehydrated they may:
- have a sunken soft spot (fontanelle) on top of their head
- have sunken eyes
- make few or no tears when they cry
- not have many wet nappies
- be drowsy or irritable.
Pēpi can quickly become dehydrated and unwell.
Always see a healthcare provider urgently if your child has vomiting or diarrhoea (possible gastroenteritis or bowel infection) and is under 6 months old.
Call Healthline — freephone 0800 611 116.
After hours and urgent medical centres — Healthpoint (external link)
Treating mild dehydration
If you are an older child or adult with mild dehydration, you can often care for yourself by drinking more fluids.
Drink water — sugary drinks such as cola or fruit juice are not as hydrating and can make problems like diarrhoea worse.
If you feel unwell and unable to drink much at one time, try taking small sips every 2 minutes. You could also suck on ice chips.
Replacing lost salts
When you sweat a lot, have been sick (vomited) or had runny poos (diarrhoea), you lose a lot of salts as well as fluids.
You may need to replace these salts as well as fluids. To do this you can drink an electrolyte (salt) solution such as Electral, Hydralyte or Pedialyte. You can buy these at a pharmacy or get them on prescription.
If you are having dialysis or your potassium levels monitored as part of your medical care, you should get medical advice before using electrolyte solutions.
Prepare electrolyte solutions according to the instructions on the packet.
Electrolyte solutions for oral rehydration — Healthify (external link)
Preventing dehydration and staying well in the heat
Sometimes you can get dehydrated, even when you are otherwise well. Things you can do avoid dehydration and other effects of being in the heat, include:
Drink plenty of fluids
- Try to drink at least 2 litres of fluids a day — fill a bottle with cold water and drink frequently throughout the day.
- Have plenty of cold drinks.
- Even if you do not feel thirsty, drink water — some health conditions and medicines can stop you feeling thirsty.
- Avoid hot, caffeinated, energy or alcoholic drinks — they can worsen dehydration.
- Eat nourishing cold foods with a high water content, such as salads and fruits.
If you are unable to drink much in one go, try sipping small amounts over a longer time.
The easiest way is to check if you are drinking enough is by looking at the colour of your wee and the amount. Except for first thing in the morning, your wee should be almost clear and there should be plenty of it. If it is a dark-yellow colour, you are not drinking enough.
Stay cool in hot weather
- Rest in a cool, well ventilated area.
- Draw your blinds or curtains.
- Use an electric fan or air conditioner set to cool.
- Turn off unnecessary lights and electrical equipment — they create heat.
- Open windows in the evening or overnight, once the temperature drops.
- Spray water or apply cool wet cloths or towels to your skin.
- Put your feet in cool water or take a cool (not cold) shower or bath.
- Sleep in another room if it is cooler.
Look out for very young tamariki and older whānau and neighbours. Check on them often to make sure they are drinking and eating well, keeping cool and taking medicines properly.
Plan your day
- Avoid going out in the heat.
- Dress down — wear lightweight, light-coloured, loose-fitting clothing made from natural fibres, like cotton or linen.
- Be SunSmart (Slip, Slop, Slap and Wrap).
- Find shade — wear a hat or take an umbrella with you for shade if you are outside on a hot day.
- Avoid extreme physical activity or exercise in the middle of the day.
Be SunSmart (Slip, Slop, Slap and Wrap) — SunSmart (external link)